Few bands tip-toe along the thin line between alt-rock and Top 40 better than the three who hit the Iowa State Fair Grandstand Sunday, Aug. 15.

Armed with sappy ballads and summer anthems, the Goo Goo Dolls, Sugar Ray and Fastball are the posterbands of the crossover movement of the late ’90s.

Both the Goos and Sugar Ray were underground hard rock acts long before they graced the “TRL” countdown.

Metal Blade, an indie label specializing in thrash metal, served as home to the pre-“Name” Goo Goo Dolls, while Sugar Ray spent their early days cranking out hard-core tunes, more Faith No More than Sublime, for soundtracks like “Escape From L.A.”

Never would these bands’ directional overhauls be more evident than at an early evening Sunday show at a state fair.

Let’s just say this: The loudest cheers of the night came during a freestyle competition when a young female member of the crowd urged Sugar Ray frontman Mark McGrath to take off his shirt.

It may not be rock purity, but it was entertainment, which seemed to be the focus of all three bands.

Fastball, sounding much more country-influenced than their records reveal, used solid singing and a string of hits to win over a crowd still awed by the new nine-story carnival attraction a few blocks away.

How well the band cruised through “All The Pain Money Can Buy” gems “Better Than It Was” and “Sooner Or Later” made you wonder how the relatively boring “The Way” became their breakthrough hit.

While “The Way” was the first true crowd pleaser of the night, the more recent “Out Of My Head,” with its clever lyrics and soothing organ accompaniment, ran away with the blue ribbon for performance.

The indisputable star of the evening, however, was Sugar Ray frontman Mark McGrath, who when not announcing his sexual inadequacies, takes the crowd in his palm and shakes them with ease.

Equal parts Jim Morrison and Vanilla Ice, McGrath could write the book on modern day stage presence. He can dance a mean Molly Ringwald, play games and even sing — so surprisingly well, in fact, that even he looks stunned sometimes.

McGrath’s charm is perfect for the new Sugar Ray sound — catchy pop songs that flirt with the hidden Korn fan in all of us.

With help from showboating guitarist Rodney Sheppard, the band also dips into everything ’80s, simple as Devo or as complex as The Police.

“Falls Apart” and “Someday” made for great early-show crowd pleasers, which allowed McGrath and crew to “play our very first single that almost ruined our careers.”

“Mean Machine” is far from complex, and not nearly as fun as “10 Seconds Down” (the second single from the band’s 1995 debut “Lemonade & Brownies”), which they didn’t play, but it painted a pretty picture of the old Sugar Ray.

During the song, DJ Homicide left his record spinner’s throne to join McGrath for an impressive improvisational take on Fatboy Slim’s famous “Funk Soul Brotha” chorus.

McGrath offered what little inspirational words he had in an intro to “Fly,” which made you think a bit more about the tune until the chorus kicked in and forced you to dance.

“Every Morning” closed out the show, which went by so fast the sun barely had time to set.

Goo Goo Dolls headlined and offered a set with more momentum changes than the fair rides that served as the backdrop to the stage.

“Iris” and “Name” are beautiful songs, but don’t quite bring chills when packaged in a plethora of punk rock.

“Long Way Down” and “Naked” were the most potent, catching the band at their musical and lyrical bests.

Johnny Rzeznik showed surprising diversity and vocal prowess, playing tunes both old and new, while bassist Robby Takac was just as enjoyable, as long as he wasn’t singing.

It may have taken an identity crisis to get there, but the Goo Goo Dolls have proven that rock can still pop.